One New York City cop must stop a bunch of machine gun-toting terrorists from robbing The Federal Reserve Bank of New York by using bombs and the subway system. Completely unbelievable. Would never happen. Could not happen.

Wait, what? Maybe it could…?

The third installment of the long-running action franchise “Die Hard” was one of the best. Following our hero John McClane as he tries to stop the brother of Hans Gruber—the guy who fell out of a window in the first one—as he tries to rob the New York Federal Reserve by bombing a subway stop and then using trucks to drive through water tunnels.

Screenwriter Jonathan Hensleigh states in the audio community for the film that while writing the script he wanted to find out how to actually rob one of the world's most important banks. The best way to do that? Probably plan a daring heist for months, right? Nope. Just walk in and ask for a tour. Yes, the building that holds the most amount of gold in the United States allowed a screenwriter to walk into the vault, let him hold a gold bar, and even told him that the nearby subway messes with security system all the time. We assume afterwards they told him where they hid the spare key (Spoiler alert: it’s under the fake rock out front).

Later, while Hensleigh was trying to figure out how to get the gold out of the city, he read that a new water duct tunnel was being built. Perfect. He added that to the finished script and turned it in.

At this point, the FBI was able to read said script with all the spare time they must have. They discovered a huge problem… All of it was possible! While writing an action movie, Hensleigh had created a very plausible plan to rob Uncle Sam. FBI agents eventually showed up at the studio’s office and started asking questions. “Die Hard With A Vengeance” was allowed to move forward but only after major changes were implemented at the Federal Reserve.

The spare key has since been moved to a secret location (it’s now under the plastic frog).